The Armed Forces Day Crossband Military/Amateur Radio Communications Test (12 May 2018) is an annual opportunity for amateur radio operators and Military Affiliate Radio Service (MARS) stations to communicate by transmitting on frequencies in their respective services and listening to the frequencies used by the other service. The 2018 event will have MARS stations from the US Army, Navy, Air Force and Coast Guard participating. Among these stations are several former US Navy vessels including the following:

Some of these stations may be using CW (Morse Code) as the transmission mode at times.

There is also an opportunity to copy a test message (usually from the Secretary of Defense) in various transmission modes including Morse Code, so you don't have to be an amateur radio operator to participate.

8 May Edit: One of the call signs being used in the event is celebrating its 100th anniversary: